G.M.
Dear M. M, I do not envy you at this time! My second son was born at 32 wks and I don't think I caught my breath for a year!!! He is the most perfect 2-1/2 year old now that you'd never know, but I remember the beginning to be nerve-wracking and awful!
When they sleep, they grow...premature or not. Sounds perfectly normal to me, from your brief description. 8 weeks is a very young baby (again, preemie or not). Some refer to the first 3 months of a baby's life as the "4th trimester" which I thought was a great way to describe it. The baby is adjusting to being outside of the womb and doesn't do much that he wouldn't have done while inside.
Ha ha ha! ENJOY THE DOWN TIME WHILE YOU CAN GET IT! And enjoy your new baby! :)